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<H2><A NAME=SECTION00054000000000000000> Program  mlstest</A></H2>
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<H6><A NAME=SubsectionMLSTEST>&#160;</A></H6>
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The program <tt> mlstest</tt> is an extensive example code
demonstrating possibilities of usage of <tt> LASPack</tt>
  routines.
It solves a Poisson problem 

in a 1D or 2D unit domain by a specified multilevel solver.
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All input parameters have to be set interactively.
The output contains the convergence history as well as the determined
middle convergence rates.
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For example, a three-grid solution by means of the V-cycle multigrid method 
with the Gauss-Seidel smoothing
(two pre-smoothing and one post-smoothing iteration)
and the ILU preconditioned CG method on the coarsest grid (20 iterations)
yields for a 65 x 65 grid on the finest level:
<PRE>  0. iteration ... accuracy =  1.0000e+00
  1. iteration ... accuracy =  4.3033e-02
  2. iteration ... accuracy =  3.3534e-03
  3. iteration ... accuracy =  2.8452e-04
  4. iteration ... accuracy =  2.4934e-05
  5. iteration ... accuracy =  2.2565e-06
  6. iteration ... accuracy =  2.0996e-07
  7. iteration ... accuracy =  1.9860e-08
  8. iteration ... accuracy =  7.6893e-09

  CPU time:    0.67 s

Middle contraction rate
  referred to one iteration:  9.677e-02
  referred to 1 s CPU time:   7.751e-13
</PRE>
In this case, the input data corresponds to:
<tt> 2</tt>, <tt> 3</tt>, <tt> 64</tt>,
<tt> 1</tt>, <tt> n</tt>, <tt> 1</tt>, 
<tt> 2</tt>, 
<tt> 2</tt>, <tt> 2</tt>, <tt> 1</tt>, <tt> 0</tt>, <tt> 1.0</tt>,
<tt> 6</tt>, <tt> 20</tt>, <tt> 3</tt>, <tt> 1.0</tt>,
<tt> 100</tt>, <tt> 1e-8</tt>.
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<P><ADDRESS>
Tomas Skalicky (skalicky@msmfs1.mw.tu-dresden.de)
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